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Aberrant crypts in human colonic mucosa: putative preneoplastic lesions
T P Pretlow1, M A O'Riordan, T G Pretlow
1Department of Pathology, Case Western Reserve University School of Medicine, Cleveland, Ohio 44106.
Journal of Cellular Biochemistry. Supplement
|January 1, 1992
Summary
Aberrant crypts, early colon cancer precursors, can be identified in rodent and human colonic mucosa. These lesions show enzyme alterations and offer a rapid bioassay for colon carcinogens.
Area of Science:
- Gastroenterology
- Oncology
- Pathology
Background:
- Aberrant crypts are recognized in methylene blue-stained colonic mucosa.
- They exhibit increased size, elliptical lumenal opening, thicker epithelium, and enlarged pericryptal regions.
- Aberrant crypt foci (ACF) are observed in rodents as early as 2 weeks after carcinogen exposure.
Purpose of the Study:
- To characterize aberrant crypts as early putative precursors of colon cancer.
- To evaluate aberrant crypts as a potential in vivo bioassay for colon carcinogens.
- To investigate the earliest genetic and biochemical alterations in aberrant crypt foci.
Main Methods:
- Identification of aberrant crypts in unsectioned, methylene blue-stained colonic mucosa from rodents and humans.
- Quantification of aberrant crypts per focus over time after carcinogen administration.
- Histochemical detection of enzyme alterations in aberrant crypts.
Main Results:
- Aberrant crypts were identified in both rodent and human colonic mucosa.
- The number of aberrant crypts per focus increased with time after carcinogen dose.
- Aberrant crypts demonstrated multiple histochemically-detectable enzyme alterations in F344 rats.
Conclusions:
- Aberrant crypts are the earliest identifiable putative precursors of colon cancer.
- Aberrant crypts provide a highly efficient in vivo bioassay for colon carcinogens.
- These lesions can be further characterized to reveal early genetic and biochemical changes preceding colon cancer.